Static Virtual LANs (VLANs)

Special VLAN Types

Monitoring Shared Resources: The Management VLAN feature shares internal switch resources with several other features. The switch provides ample resources for all features. However, if the internal resources become fully subscribed, the Management VLAN feature cannot be con- figured until the necessary resources are released from other uses. For information on determining the current resource availability and usage, refer to the appendix titled “Monitoring Resources” in the Management and Configuration Guide for your switch.

VLAN 20 (Management VLAN)

Even though the ports on the Management VLAN link do not belong to any of the VLANs in the mesh, the link will be blocked if you enable Spanning Tree. This is because Spanning Tree operates per-switch and not per-VLAN.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Mesh Domain

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Includes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Membership in

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Three VLANs

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

VLAN 10

VLAN 30

VLAN 40

Switch

 

Switch

 

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Figure 2-37. Example of Inadvertently Blocking a Management VLAN Link by Implementing Spanning Tree

Voice VLANs

Configuring voice VLANs separates voice traffic from data traffic and shields your voice traffic from broadcast storms. This section describes how to configure the switch for voice VLAN operation.

Operating Rules for Voice VLANs

You must statically configure voice VLANs. GVRP and dynamic VLANs do not support voice VLAN operation.

Configure all ports in a voice VLAN as tagged members of the VLAN. This ensures retention of the QoS (Quality of Service) priority included in voice VLAN traffic moving through your network.

If a telephone connected to a voice VLAN includes a data port used for connecting other networked devices (such as PCs) to the network, then you must configure the port as a tagged member of the voice VLAN and a tagged or untagged member of the data VLAN you want the other net- worked device to use.

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